An assembly for both rotatably driving the suction draw-off tube and operating the slitter mechanism of a circular knitting machine

ABSTRACT

The present invention provides a simple assembly easily installable on a specific type of circular knitting machine, with substantially no modification thereof, for actuating a vertically-reciprocable non-rotating fabric-receiving slitter control tube disposed within the needle cylinder of the machine for operating a slitter mechanism at the upper end of the cylinder. The assembly also rotatingly drives a fabric-receiving suction draw-off or accumulator tube coaxially aligned beneath the control tube in synchronism with the needle cylinder for preventing twisting of long lengths of tubular fabrics knitted on the machine.

Elite States Patent [191 Butler AN ASSEMBLY FOR BOTH ROTATABLY DRIVING THE SUCTION DRAW-OFF TUBE AND OPERATING THE SLITTER MECHANISM OF A CIRCULAR KNITTING MACHINE Inventor:

Vaughn H. Butler, Harriman, Tenn.

Burlington Industries, Inc., Greensboro, NC.

June 28, 1972 Assignee:

Filed:

Appl. No.:

US. Cl 66/147, 66/149 S Int. Cl. D04b 35/34, D04b 15/92 Field of Search 66/149 S, 150, 147, 153,

[56] References Cited UNITED STATES PATENTS 3,667,257 6/1972 Butler 66/149 S 3,668,900 6/1972 Peet 66/149 S 3,670,528 6/1972 Fregeolle 66/147 FOREIGN PATENTS OR APPLICATIONS 1,964,627 7/1970 Germany 66/149 S 3,823,582 [451 July16,1974

1,296,979 11/1972 Great Britain 66/1498 378,452 7/1964 Switzerland 66/147 Primary ExaminerW. C. Reynolds Assistant ExaminerA. M. Falik Attorney, Agent, or Firm-Cushman, Darby &

Cushman [57] ABSTRACT The present invention provides a simple assembly easv ily installable on a specific type of circular knitting machine, withsubstantially no modification thereof, for actuating a vertically-reciprocable non-rotating fabric-receiving slitter control tube disposed within the needle cylinder of the machine for operating a slitter mechanism at the upper end of the cylinder. The assembly also rotatingly drives a fabric-receiving suction draw-off or accumulator tube coaxially aligned beneath the control tube in synchronism with the needle cylinder for preventing twisting of long lengths of tubular fabrics knitted on the machine.

4 Claims, 5 Drawing Figures BACKGROUND AND BRIEF DESCRIPTION OF INVENTION The present invention provides for a specific arrangement for driving a rotatable or oscillatable (sometimes called reciprocable) accumulator or fabric draw-off tube member within a circular knitting machine in which there must be a separation of the accumulator tube member from the needle cylinder because of the presence of an upper fabric-receiving non-rotating vertically-reciprocable tube member located within the needle cylinder and associated with a slitting mechanism carried by the machine within the cylinder.

It is known in this art to provide for so-called accumulator or draw-off tube structures for circular knitting machines for the purpose of imparting rotation or oscillation to lower end portions of relatively long knitted tubular articles being produced within such machines to avoid twisting of such articles. The rotation or oscillation of such tube structures typically is achieved by direct connection with the cylinder assembly of the, machine, so that a long tubular knitted fabric is maintained in an untwisted condition throughout its very long length during its manufacture. Prior art representative of the state of the art on such accumulator tube assemblies is my copending application Ser. No. 1,531, filed Jan. 8, 1970, as well as the patent to Shields, U.S. Pat. No. 3,550,403.

It also has recently become known in the art to provide for installation of various forms of slitting mecha nisms within circular knitting machines so as to provide for a controlled longitudinal slitting of a tubular fabric being knitted by the machine. The type of slitting mechanism with which this invention is concerned is one in which control and actuation of one or more cutting elements is effected by a non-rotating verticallyreciprocable fabric-receiving tube member suspended within the cylinder assembly of the machine. The cutting elements, of which at least one is vertically reciprocable, are carried in a vertical slot in a ring fastened within the upperend of, and rotatable with, the needle cylinder. Butts on the cutting elements ride in circumferential cam grooves in the non-rotating tube member. One of the cam grooves has a zig-zag configuration to impart vertical cutting reciprocation to the corresponding cutting element on rotation of the latter with the cylinder.

This type of slitter mechanism requires an actuating mechanism for lifting and lowering the non-rotating tube member to move the cutting elements into and out of cutting engagement with the fabric. The internal diameter of the non-rotating tube member generally corresponds with the internal diameter of the accumulator tube member so that a knitted fabric can move smoothly downwardly through both tube members as it is being knitted by the machine. However, because the upper slitter-operating tube member is non-rotating, while the lower accumulator tube member must rotate or oscillate in synchronism with the needle cylinder, and because the non-rotating tube member requires an additional actuation in vertical reciprocations to carry out its function of controlling the slitting mechanism,

it is impossible to arrange a single, continuousfabricreceiving tube member within the machine. Further, it is necessary to provide for a rotational driving of only the accumulator tube member while providing for a lifting and lowering of the non-rotating tube member.

Certain arrangements have been designed for specific circular knitting machine constructions for carrying out the various functions just described. A known prior art arrangement e.g. as disclosed in U.S. Pat. No. 3,670,508 requires that a complete complicated housing assembly carrying a drive train and crank and lever mechanisms must be installed beneath and connected to the cylinder assembly, to the non-rotating tube member, and to a lower accumulator tube of the machine to provide for drive of the accumulator tube by and in synchronism with the cylinder and to provide for the lifting and lowering of the non-rotating tube member associated with the slitting mechanism of the machine. However, it is not possible with certain designs of circular knitting machines to install such a complete housing assembly beneath the cylinder assembly of the machine without making major modifications to the machine itself or the place in which it is operating. For example, a Reading Mark III circular knitting machine includes an outer casing structure below its cylinder assembly which surrounds accumulator tube portions. If a slitting mechanism of the type described-is installed on the machine, there is no room for attachment of a complete housing assembly of the type discussed above even though there are side openings in the aforesaid casing structure. Moreover, the drive train carried by such housing assembly cannot be directly connected to the needle cylinder of a Reading Mark Ill circular knitting machine. Thus, a housing assembly of the type described cannot be used on such a knitting machine without major costly modifications of the latter.

The present invention provides for ready adaptation of a slitting mechanism of the type described to a circular knittig machine of the type described. This is accomplished with a relatively simple bracket assembly carrying components associated with an accumulator tube member and the non-rotating tube member of the slitting mechanism. The bracket is adapted to be mounted externally of an accumulator-surrounding casing below the needle cylinder of a Reading Mark III circular knitting machine with the aforesaid components extending through an existing side aperture of the casing so that there is no requirement for any substantial modification of the machine to install the assembly. The bracket assembly is provided with a relatively thin support plate element which can be easily inserted between the lower end of the non-rotating tube member and the uppr end of an accumulator tube member. The plate element carries a ring gear means attachable to the upper end portion of an accumulator tube member for driving and supporting the latter. The main body of the bracket assembly is mounted externally of the machine casing and carries a simple gear train, consisting of a pinion gear means meshing with the ring gear means and a bevel gear means mounted for driving rotation with the pinion. gear means so as to receive a driving input from a main drive gear associated with the circular knitting machine. This drive chain rotates or oscillates the accumulator tube member in synchronism with the knitting cylinder.

In addition, the bracket assembly carries a simple lever arm assembly which includes means for engaging a lower end of the non-rotating tube member which operates a slitting mechanism carried by the machine. The lever arm assembly includes a lever which is pivotally mounted on the bracket assembly so that one end of the lever can be actuated, in a programmed arrangement, by a cam on the main cam shaft of the knitting machine. The lever carries a pin which engages the lower end of the non-rotating tube member for lifting and lowering the latter. The program is such as to lift the non-rotating tube member to raise the cutting elements of the slitting mechanism into operative cutting engagement with fabric being produced by the machine and to lower the tube member so as to lower the cutting elements out of such cutting engagement, in accordance with a desired program of operation.

These and other features and advantages of the present invention will become apparent in the more detailed discussion which follows. In that discussion reference will be made to the accompanying drawings as briefly described below. a

FIG. 1 is a fragmentary elevational view, partly in section, of a circular knitting machine embodying this invention, only those parts being shown which are necessary'for an understanding of this invention.

FIG. 2 is an elevational view of one of the blades of the slitter mechanism shown in FIG. 1.

FIG. 3 is a fragmentary sectional viewtaken substan-' tially on line 3-3 of FIG. 1 but omitting casing structure. I

FIG. 4 is a fragmentary sectional view taken substantially on line 4-4 of FIG. 1, but omitting the slitter mechanism control tube.

FIG. 5 is a fragmentary sectional view taken substantially on line 55 of FIG. 1.

Referring now to the drawings, there is shown portions of a circular knitting machine having a needle cylinder provided with longitudinal exterior slots 12 for reception of the usual needles and jacks (not shown). The cylinder 10 is connected by a key 14 to a hub of a bevel gear 16 recessed into the bed 18 of the machine. The cylinder 10 is driven for rotation or oscillation in known manner by a horizontal main drive shaft somewhat elongated vertical pins 26 which extend freely through guide apertures in the gear 16 and bear upon e upper ring of a ball race 28 snugly but slidably received in a depending counterbored boss 30 on the bed 18. The race 28, in turn, rests on the upper end of a tube 32 which is raised and lowered, in known manner by means not shown, to correspondingly raise and lower the needle cylinder 10 to achieve stitch length variation for shaping a tubular fabric, e.g. a stocking or panty hose, being knitted on the machine.

An enlarged tubular casing 34, having a large side aperture 36 opposite the gear 24, depends from the bed 18 in alignment with the cylinder 10. Tubular fabric knitd on the machine by its knitting instrumentalities (not shown) adjacent the upper end of the cylinder 10 is drawn downwardly therethrough by appropriate draw-off means, here shown as being effected by the application of suction to the lower end of a tube 38 of a draw-off or accumulator device of the type disclosed in the aforesaid copending application and patent. The

tube 38, preferably of transparent plastic, is disposed within the casing 34 and terminates at its upper end well below the cylinder 10. The apparatus described thus far is conventional, except accumulator tubes usually extend upwardly to the upper end of a needle cylinder and are connected directly thereto for rotation therewith.

The tube 38 terminates below the cylinder 10 because of the presence of slitting mechanism within the cylinder which is moved into and out of operative engagement with fabric being knitted by a non-rotating slittercontrolling tube 40 positioned coaxially within the cylinder 10. Secured, as by screws 42, within the upper end of the cylinder 10 is a knife-carrying ring 44 having a slot 46 'in its inner surface parallel to the ring axis. It will be noted that the ring 44 serves as a bearing to support and guide the upper end of the tube 40. Preferably the upper ends of the cylinder 10, the ring 44, and the tube-'40 are concave-conical with merging,

smooth surfaces as shown in FIG. 1 for unobstructed passage of the tubular fabric being knitted downwardly through the tube 40. Slidably carried in the slot 46 is a pair of cutting blades or knives 48, 50. One 48 has a hook-shapedupperend facing the oncoming fabric and has an inclined downwardly-facing sharp edge 52 which cooperates with a slightly differently inclined upwardly-facing sharp edge 54 on the other blade to cut and slit fabric passing between the sharp'edges.

The blade 50 has a radially-inwardly-directed butt 56 riding in an exterior circumferential groove 58 in the tube 40, while the blade 48 has a similar but lowerpositioned butt 60 riding in a lower exterior circumferential cam-groove 62 in the tube 40. The groove 62 has a zig-zag configuration so that relative rotational movements between the knives 48 and 50 and the non rotating tube 40, effected by rotational movements of the cylinder 10, cause the knife 48 to reciprocate vertically to cooperate with knife 50 to uninterruptedly cut the fabric vertically parallel to the axis of the cylinder. In the position shown, the knives 48 and 50 are positioned for cutting engagement with the fabric, but it will be seen that by moving the tube 40 downwardly the knives can be retracted completely into the slot 46 and 64 which carries most of the mechanism for operating the tube 40 and driving the accumulator tube 38. This bracket assembly 64,is attachable to the machine with substantially no modification of the latter while the operating components carried by the assembly are readily connectable to appropriate parts of the machine by the addition of simple elements.

The assembly 64 includes an elongated narrow plate 66 secured by suitable angle brackets 68, 70 and cap screws 72 to the side of the housing 22 below the shaft 20 and adjacent the aperture 36 in the casing 34. Preferably the hole 74 (FIG. 3) in the plate 66 for securing the bracket 70 thereto by screw 72 is elongated transversely of the plate for adjustment purposes. Fastened in a countersink at one side of the plate 66, as by screws 74, is a gear-carrying plate 76 which projects through the aperture 36 between the adjacent ends of the tubes 38 and 40. The plate 76 has a large central aperture coaxial with the tubes 38 and 40 within which is appropriately fixed, as by staking, a sleeve bushing 78 which depends therebelow. Rotatably received in the bushing 78 is a short tube section 80 fixed at its upper end, as by staking, to a ring gear 82 which rides on top of the bushing 80. The upper end of the accumulator tube 38 snugly receives the lower end of the tube section 80 and is fastened thereto and supported therefrom by any appropriate means, such as a clamp ring 84.

The gear 82 meshes with a pinion 86 journalled on an upright post 88 suitably secured to the plate 66. Also journalled on the post 88 above the pinion 86 and appropriately keyed thereto is a bevel pinion 90 which meshes with a bevel gear 92 coaxially attached to the side of the gear 24 by any appropriate means, e.g. screws 94. The ratios of the gears 82, 86, 90 and 92 are such that the gear 82, and hence the accumulator tube 38, rotates in synchronism with the needle cylinder 10.

The lower end of the slitter control tube 40 slidably but snugly fits within the upper end of the short tube section 80 which acts as a bearing to support and guide the tube 40. The latter is restrained against rotation and lifted and lowered to move the knives 48, 50 into and out of operative engagement with the fabric by a radial pin 96 snugly but rotatably fitting a socket in an exterior boss 98 on the tube 40. The other end of the pin 96 is fixed to the side of a lever 100, intermediate its ends, having one end secured by a pivot pin 102 to the upper end of a bracket 104 fastened, as by a screw 106, to the plate 66 It will be seen that vertical movement of the lever 100 about the pin 96 will lift or lower the control tube 40.

The lever 100 is moved in a programmed arrangement by a cam 108 on the main cam drum 110 of the machine. For this purpose a link 112 connects the end of the lever 100 remote from its pivot 102 with one end of another lever 114 pivotally mounted intermediate its ends, as by an appropriate bracket 116 secured to a casing (not shown) of the machine. The other end of the lever 114 is provided with a follower 118 biased to ride the drum 110 by a tension spring 118' connected to the lever 114.

What is claimed is:

1. In a circular knitting machine of a type having (a) a needle cylinder mounted for rotation during a knitting operation from a horizontal main drive shaft having an end spaced vertically below, and horizontally from the peripheral outline of, the cylinder, (b) a reciprocating fabric-slitting mechanism carried by the cylinder and operated by a fabric-receiving non-rotating vertically movable tube member carried within the cylinder to slit tubular fabric longitudinally as it is knit by the machine, (c) a suction draw-off tube member coaxially aligned with and disposed below the non-rotating tube member, whereby said members have spaced opposed ends, (d) a cylindrical casing below the cylinder enclosing the draw-off tube member and having an access opening adjacent the end of the main drive shaft and (e) drive means for rotating the draw-off tube member in synchronism with the cylinder, the improvement in said drive means comprising:

a bracket assembly mountable on the machine outside the casing adjacent the opposed ends of the tube members and adjacent the end of the main drive shaft, said bracket assembly having:

a support plate element extendable through the access opening and positionable adjacent the opposed ends of the tube members and having a circular aperture coaxial therewith;

a ring gear means having a fabric-receiving tubular extension joumalled in said aperture and extending therebelow, said extension being adapted to receive the lower end of the non-rotating tube member to provide bearing support therefor and being attachable to the upper end of the draw-off tube member for supporting the latter;

pinion gear means mounted on said plate element and meshing with said ring gear means; and

bevel gear means attachable to the main drive shaft adjacent the end thereof and meshing with said pinion gear means for drivingly rotating the draw-off tube member in synchronism with the cylinder assembly.

2. The structure defined in claim 1 wherein the bracket assembly further includes a lever arm assembly mounted to the plate element and engageable with the non-rotating tube member for restraining rotation thereof and for lifting and lowering the non-rotating tube member to render the slitting mechanism operative or inoperative.

3. The structure defined in claim 2 wherein the lever assembly includes a pin radially engageable in a socket in the exterior of the non-rotating tube member.

4. The structure defined in claim 2 in which the ma chine has a main cam drum and including means operatively connectable to the lever assembly and to the drum for rendering the slitting mechanism operative or inoperative. 

1. In a circular knitting machine of a type having (a) a needle cylinder mounted for rotation during a knitting operation from a horizontal main drive shaft having an end spaced vertically below, and horizontally from the peripheral outline of, the cylinder, (b) a reciprocating fabric-slitting mechanism carried by the cylinder and operated by a fabric-receiving non-rotating vertically movable tube member carried within the cylinder to slit tubular fabric longitudinally as it is knit by the machine, (c) a suction draw-off tube member coaxially aligned with and disposed below the non-rotating tube member, whereby said members have spaced opposed ends, (d) a cylindrical casing below the cylinder enclosing the draw-off tube member and having an access opening adjacent the end of the main drive shaft and (e) drive means for rotating the draw-off tube member in synchronism with the cylinder, the improvement in said drive means comprising: a bracket assembly mountable on the machine outside the casing adjacent the opposed ends of the tube members and adjacent the end of the main drive shaft, said bracket assembly having: a support plate element extendable through the access opening and positionable adjacent the opposed ends of the tube members and having a circular aperture coaxial therewith; a ring gear means having a fabric-receiving tubular extension journalled in said aperture and extending therebelow, said extension being adapted to receive the lower end of the nonrotating tube member to provide bearing support therefor and being attachable to the upper end of the draw-off tube member for supporting the latter; pinion gear means mounted on said plate element and meshing with said ring gear means; and bevel gear means attachable to the main drive shaft adjacent the end thereof and meshing with said pinion gear means for drivingly rotating the draw-off tube member in synchronism with the cylinder assembly.
 2. The structure defined in claim 1 wherein the bracket assembly further includes a lever arm assembly mounted to the plate element and engageable with the non-rotating tube member for restraining rotation thereof and for lifting and lowering the non-rotating tube member to render the slitting mechanism operative or inoperative.
 3. The structure defined in claim 2 wherein the lever assembly includes a pin radially engageable in a socket in the exterior of the non-rotating tube member.
 4. The structure defined in claim 2 in which the machine has a main cam drum and including means operatively connectable to the lever assembly and to the drum for rendering the slitting mechanism operative or inoperative. 